title: Esophageal circumferential en bloc endoscopic submucosal dissection: assessment of a new technique.
abstract: BACKGROUND
  Endoscopic esophageal piecemeal mucosectomy for high-grade dysplasia on Barrett's esophagus leads to suboptimal histologic evaluation, as well as recurrence on remaining mucosa. Circumferential en bloc mucosal resection would significantly improve the management of dysplastic Barrett's esophagus. Our aim was to describe a new method of esophageal circumferential endoscopic en bloc submucosal dissection (CESD) in a swine model.
  
  
  METHODS
  After submucosal injection, circumferential incision was performed at each end of the esophageal segment to be removed. Mechanical submucosal dissection was performed from the proximal to the distal incision, using a mucosectomy cap over the endoscope. The removed mucosal ring was retrieved. Clinical, endoscopic, and histologic data were prospectively collected.
  
  
  RESULTS
  Esophageal CESD was conducted on 5 pigs. A median mucosal length of 6.5 cm (range, 4 to 8 cm) was removed in the lower third of the esophagus. The mean duration of the procedure was 36 minutes (range, 17 to 80 min). No procedure-related complication, including perforation, was observed. All animals exhibited a mild esophageal stricture at day 7, and a severe symptomatic stricture at day 14. Necropsy confirmed endoscopic findings with cicatricial fibrotic strictures. On histologic examination, an inflammatory cell infiltrate, diffuse fibrosis reaching the muscular layer, and incomplete reepithelialization were observed.
  
  
  CONCLUSIONS
  CESD enables expeditious resection and thorough examination of large segments of esophageal mucosa in safe procedural conditions, but esophageal strictures occur in the majority of the cases. Efficient methods for stricture prevention are needed for this technique to be developed in humans.
authors.affiliation: Departments of *Gastroenterology †Pathology, Cochin Hospital, Paris, France.
authors.forename: Maximilien
authors.initials: M
authors.lastname: Barret
authors.forename: Carlos Alberto
authors.initials: CA
authors.lastname: Pratico
authors.forename: Frédéric
authors.initials: F
authors.lastname: Beuvon
authors.forename: Luigi
authors.initials: L
authors.lastname: Mangialavori
authors.forename: Ariane
authors.initials: A
authors.lastname: Chryssostalis
authors.forename: Marine
authors.initials: M
authors.lastname: Camus
authors.forename: Stanislas
authors.initials: S
authors.lastname: Chaussade
authors.forename: Frédéric
authors.initials: F
authors.lastname: Prat
mesh_terms: D000818:Animals; D001471:Barrett Esophagus / Q000473:pathology / Q000601:surgery*; D004210:Dissection / Q000379:methods; D004435:Eating; D004938:Esophageal Neoplasms / Q000473:pathology / Q000601:surgery; D004945:Esophagoscopy / Q000379:methods*; D005260:Female; D008297:Male; D011230:Precancerous Conditions / Q000473:pathology / Q000601:surgery; D034421:Sus scrofa; D013552:Swine